Gagne didn't return after the first-period play. Another Lightning player, defenseman Pavel Kubina, didn't play in the third period after getting hit by Capitals forward Jason Chimera late in the second; Chimera was called for roughing on the play.

Lightning spokesman Brian Breseman said both players would be re-evaluated Saturday. Breseman wouldn't say anything about the nature of either player's injury.

Game 2 is Sunday at Washington.

The side of Gagne's helmet slammed against the ice when he dropped down after being lifted off his feet on a hit in a corner by Capitals defenseman Scott Hannan, 8:22 into the first period Friday night. Gagne didn't do anything to break his fall.

Gagne has a history of head injuries and played in only 25 games in the 2007-08 season, when he was with Philadelphia.

Gagne stayed down on his back, motionless, for a couple of minutes Friday while being attended to by medical personnel. A stretcher was wheeled onto the ice, but Gagne eventually rose and headed toward the locker room with help from two people.